This is based on a post to the Homebirth UK group - please excuse lack of editing, but better to have it onsite and unedited than languishing in my 'to do' folder!
Full term for a 'normal' pregnancy is defined by the World Health Organization as 37 - 42 weeks. Until recently most health authorities would support bookings for home births between those dates. However,recently some health authorities have changed their policies to support homebirth only from 38 weeks onwards.
There are some extra risks with 'early' homebirth, but the risks for a baby born after a spontaneous, natural labour at home are probably lower than for many babies born after a planned hospital birth. Once you have assessed the risks, and decided how they apply to your family, you can make your decision.
The most worrying increased risk is of breathing problems. It is true that the risk of breathing problems increases the younger a baby is, but there are other factors which are very relevant, too. For example, much research has shown that babies born by elective caesarean who have not experienced labour are far more prone to breathing trouble than babies who have experienced labour (eg see [2 and 3] below). This led to a rash of advice to hospitals not to perform elective sections before 38 weeks because of the risks of breathing problems. One by-product of this was that some hospitals decided that, if elective section was too risky before 38 weeks, then crikey - home birth certainly must be! Doh... Yet a baby who is born vaginally, at home, has been primed by the labour to breathe, has had excess fluid squeezed out of its lungs by contractions, and has a greater lung volume than a baby born by caesarean as a consequence.
Another relevant factor is the use of drugs in labour. Opiates such as pethidine are known to have significant risks of depressing the baby's breathing. They are used in around a third of hospital births, but only in around 4% of births at home. A mother who knows that her baby is a few weeks early, and who chooses to remain at home, might also choose to reduce the risks of breathing problems by avoiding opiates. Again, the baby born at home after an opiate-free labour at 36 weeks, is in a completely different situation to the baby under the influence of these drugs. Note that most babies born after the administration of Pethidine will not suffer breathing difficulties, but it does approximately double the risk of them occurring. Naloxone is an antidote which can ameliorate the short-term depressive effect on the baby's breathing, but it wears off quite quickly and does not seem to help with the longer-term detrimental effect on the baby's feeding.
It should also be considered that spontaneous labour is partly triggered by hormonal signals from the baby's body which indicate that its lungs have matured. Babies born by elective caesarean have had not had this opportunity to instigate labour. If a woman goes into spontaneous labour at 37 weeks then there would, logically, be a higher chance that her baby's lungs were mature, than if the labour was induced or the baby born by elective CS.
Risk 2 is that the 36-weeker will have trouble maintaining its body temperature. There are other ways of dealing with this apart from putting the baby on a hospital heat pad - such as snuggling up to mum, skin-to-skin under a large fluffy towel, in a warm room, with a hat on its head to help it keep warm.
Risk 3 is that a 36-weeker would have trouble establishing feeding - true, the sucking reflex may not be as well developed in some babies, although most are fine, but if that happens - you have plenty of time to realise it and work around it, cup- or spoon-feeding, and transferring into hospital if necessary.
And if there is a problem with establishing breastfeeding, a hospital is often not the best place to work at it. The environment is not relaxing for many mothers and babies, and that feeling of being constantly scrutinised just can't help. Not to mention the fact that breastfeeding 'support' in most UK hospitals probably accounts for our national low breastfeeding rate.
For example, it is still very common in hospital for midwives to actually try to 'help' women by putting the baby on your breast themselves, ie midwife holds baby and/or breast and brings the two together. This is despite the fact that women given such 'hands on' breastfeeding 'help' are significantly less likely to be still breastfeeding at 6 weeks than women given 'hands off' support. You will find that no breastfeeding counsellor trained by the NCT, La Leche League or Breastfeeding Network will ever touch your breasts or your baby's head when helping you to breastfeed - and they spend far longer training in breastfeeding support than midwives do.
If you have a breastfeeding problem, a specialist breastfeeding counsellor can give you support over the phone or may visit you at home. See Breastfeeding Contacts for more info.
In summary, the only good reason I can see for accepting hospital birth for an early baby would be worries about breathing difficulties. The study  below found that, after 'uncomplicated preterm labour with membranes intact', 4.2% of babies born at 36 weeks had breathing difficulties. We don't know how many of these babies were exposed to opiates in labour, nor how many were subjected to additional stresses known to make respiratory distress more likely, such as vigorous suctioning at birth (ironic, isn't it? It's been proven to cause the exact problem it's supposed to prevent, but in some places it's still over-used...). Personally I think that only an individual mother can decide whether a 1 in 20 risk that her baby will need to transfer to hospital after birth because of breathing difficulties is a sufficient reason to plan a hospital birth or not. It's not for anyone else to make that decision for her.
When home births were more common in the UK, the cut-off point was normally 36 weeks. In 1967 the Ministry of Health published a booklet, "Safer Obstetric Care", which included criteria for "low-risk" pregnancies which should be managed at home or in a GP unit. One criterion was that the pregnancy was 36 weeks' gestation or more. This is discussed in Julia Allison's book about community midwives in Nottingham, "Delivered at Home". Funny how something can go from being 'low-risk' to panic material in just 30 years!!!
It can be hard to get specific figures on the risks a baby faces when born earlier than the average, but there has been one recent review which is helpful. Escobar and colleagues looked at the rates of breathing difficulties and readmission to hospital amongst babies born at 35 weeks, 36 weeks, 37 weeks and 38-40 weeks. The abstract is copied below, with a link to the full text of the article. They found that, overall, babies born at 37 weeks were twice as likely to receive supplemental oxygen for an hour or more, compared to babies born at 38-40 weeks - a similar rate, incidentally, for babies born by caesarean section compared to babies born vaginally, at any gestation. And a baby born at 36 weeks was twice as likely as one born at 37 weeks, to receive supplemental oxygen. Clearly a baby born early does face some increased risks, but the issue is how great those risks are. Some of these early babies were not breathing well on their own, and received oxygen support until they had established a good breathing pattern. Midwives in the UK normally bring oxygen to homebirths, and it is also available in ambulances during transfer to hospital. This is not a situation where the baby just does not breathe - it's a situation where the baby breathes, but not very well, and is transferred to hospital for more support. Escobar cites the overall chances of a baby experiencing respiratory distress as 22.1% at 33-34 weeks' gestation, 8.3% at 35 - 36 weeks, and 2.9% at term (37-42 weeks). Bear in mind that these are overall figures, including babies born by caesarean section, multiple birth, and after the administration of opiates, so you would expect the rates for a straightforward unmedicated vaginal birth to be lower.
Escobar and colleagues conclude: "Acute respiratory distress is the most common clinical entity seen in late preterm infants. This risk drops sharply beginning at 36 completed weeks of gestation."
If your personal cut-off point for having a home birth is 37 weeks (as it still is for most health authorities) then you have every right to remain at home if you were to go into labour then. For most women, this question will not arise, as the majority will go into labour after 38 weeks anyway. You might choose to avoid having a confrontation during your antenatal care, but if you go into labour before 38 weeks, so simply call and state that you are staying at home, and you expect a midwife to attend. A supportive birth partner could take over with the negotiations once you have stated your wishes. Alternatively you might prefer to clarify the situation during your pregnancy, and a sample letter which could be sent to the Health Authority is copied below.
If you don't get the reply you want, contact AIMS quickly - don't struggle on alone and put yourself through unnecessary stress. AIMS are the experts in helping women get the maternity care they need. See www.aims.org.uk for contact details.
This letter could be addressed to the Head of Maternity, and copied to the Department of Health, your hospital's Maternity Services Liaison Committee, your local homebirth support group, AIMS, and even your MP if you feel so motivated.
"Dear Head of Maternity,
I am booked for a home birth with the A-team of midwives, and my due date is (date). I understand that your unit does not recommend home birth prior to 38 weeks gestation, which I find surprising as the World Health Organisation's definition of 'term' is 37 - 42 weeks, and most health authorities support home birth from 37 weeks' gestation.
If I go into labour from 37 weeks' gestation then I have decided that I will remain at home for the labour and birth, unless there is a particular reason for transfer which emerges on the day. I am not prepared to accept hospital confinement solely on the basis of being under 38 weeks' gestation.
I would therefore appreciate it if you would make arrangements for the home birth kit to be delivered to my home prior to my 37 weeks date, which is (date). I am sure you will agree with me that it could be disastrous if a midwife was called to attend my home birth, but did not have the necessary resuscitation equipment available to her.
I look forward to your reply, Yours... "
I was told that I would have to go into hospital until I was 38 weeks. Well, I put my foot down and told them that as a Baby is classed as Fullterm at 37 weeks, I would not budge from home unless there was a problem....well, they brought the Homebirthkit round on the day I was 37 weeks:) He didn't come until 38 weeks, lol, different story!
Suzanne's first baby, Kira, was born at home at 37 weeks, weighing 5lb 8oz.
Miriam's first baby was born at home at 36+3 weeks, weighing 6lb 11oz. Miriam had a waterbirth and baby Ellie was in fine condition, but unfortunately went to hospital a few days later because of jaundice and feeding problems.
Melanie Dunne went into labour at 36 and a half weeks, and found herself labouring in hospital rather than at home as she had hoped. Pethidine administered shortly before the birth left baby Alice slow to breathe, but it's clear that her birth was still a triumph despite not going according to plan.
34 and a half weeks: this mother was planning to stay at home after 36 weeks, but when she went into labour at 34 1/2 weeks, it progressed so quickly that she had no time to get to hospital. Her baby was in excellent condition and did not need to go to hospital after the birth.
Regarding the 38 weeks rule to go into hospital....... If you feel that the baby is fine, I think I would opt to stay at home and hope that the midwife you had was sensible and okay about it. 37 weeks certainly makes me feel absolutely fine about a birth at home, but plenty of babies are fine at 36 weeks. You will know what is best for you and don't be bullied into anything you do not feel comfortable with. If your partner is uncomfortable, that may be a reason to choose to go into hospital.
If the baby is born very soon, just be aware that some babies born around this time weaken and struggle a bit to feed. If by the third day you milk is in and your baby a bit sleepy and not that interested in feeding, you may need to cup feed him/her for a few days with expressed breast milk. This can be very tiring, expressing and feeding every 3 hours or so, but you should get advice from the midwives. Some babies get tired out (not the resources of 38+ weeks), some do not.
I supported someone recently for a lovely homebirth at 35 weeks. Baby needed admitting to hospital for added feeding support and rest for Mum after a week, because they were all soooo weary. She left hospital 10 days later after several days of tube EBM and was fully breastfeeding, which frankly surprised me. I thought she just would not manage it and may have to supplement, but she did it and so did baby. Lovely.
Debs Purdue, Independent Midwife
From a midwife quoted on Ronnie Falcao's wonderful US midwifery archives:
To a fellow midwife whose client was threatening labour at 35 weeks +5 days:
1. is she GBS pos or does she have some other bacterial/nutritional problem that is causing the babe to come early?? that will cause problems for the baby. Keep a close eye on the neonate for signs of infection and get help if you're worried.
2. almost -36 weekers usually do well at first but will not have a good sucking reflex. If you decide to do it at home, have a professional quality electric breast pump and sterile syringes to dropper feed with.
3. the baby must be kept consistently warm (no drafts, good heat source in the house) as it will not have extra body fat. Plan to have hot towels, receiving blankets, hot water bottles, heating pads, etc. Keep mom and baby nested skin to skin (a la Kangaroo Care). A good quality sling is helpful to carry baby.
4. Parents should be very motivated to do the intensive caring that will be needed to keep the baby hydrated. If there is a conscientious grandmother in the picture, that helps a lot, too.
5. By Day 3 the baby will become very jaundiced and sleepy (very immature liver). The dropper feeding needs to continue despite the sleepiness.
If you want some inspiration about preemies doing well despite being born under very harsh conditions, read "The Dionne Years" by Pierre Burton (Canada). It is the story of the Dionne quintuplets, born at about 30 weeks and all weighing just over a pound. The midwives kept them alive on the oven door of the wood stove (this was in the l930s) by feeding them donated breastmilk from the village women.
It is a big commitment of time and energy to watch over these little ones.
 Am J Obstet Gynecol 2000 Aug;183(2):356-60
Should intravenous tocolysis be considered beyond 34 weeks' gestation?
Jones SC, Brost BC, Brehm WT.
Department of Obstetrics and Gynecology, Keesler Medical Center, Keesler
Air Force Base, MS, USA.
OBJECTIVE: Our purpose was to assess the incidence of respiratory distress syndrome in nonindigent women with uncomplicated preterm labor between 34 and 36 weeks' gestation.
STUDY DESIGN: All women seen between June 1, and April 15, 1999, with uncomplicated preterm labor and intact membranes and delivering between 34 and 36 weeks' gestation were analyzed. Rates of respiratory distress syndrome after delivery were calculated. A chi(2)analysis was performed, and a P value of <.05 was considered statisticallysignificant.
RESULTS: Respiratory distress syndrome was noted in 8 (17.4%)of 46 infants delivered at 34 weeks' gestation, in comparison with 5 (6.3%)of 80 infants and 7 (4.2%) of 165 infants delivered at 35 and 36 weeks'gestation, respectively (P =.008). The rate of respiratory distress syndrome after delivery at 34 weeks was significantly higher than at 35 weeks (P=.048).
CONCLUSION: The rate of respiratory distress syndrome after deliveryat 34 weeks is significantly higher than at either 35 or 36 weeks' gestation in our population.
PMID: 10942469 [PubMed - indexed for MEDLINE]
 Obstet Gynecol 1985 Jun;65(6):818-824
Respiratory morbidity benefit of awaiting onset of labor after electivecesarean section.
Cohen M, Carson BS.
Respiratory morbidity in term neonates is an important complication ofelective cesarean delivery. The effect of preceding labor on the incidenceand severity of respiratory morbidity in two comparable groups of neonates, 107 with and 80 without labor and with no predisposing factors to respiratory morbidity, was evaluated. Transient tachypnea of the newborn accounted for the majority of cases in term neonates. Respiratory morbidity occurred less frequently in neonates delivered after the onset of labor compared with those delivered before labor (11.2 versus 30%, P less than.002). The risk of respiratory morbidity decreased 1.5 times for each weekof advancing gestational age. The presence of labor significantly reduced the risk of respiratory morbidity, independently of gestational age (P less than .03), and disease was less severe in neonates born during labor. Awaiting the onset of labor appears to be beneficial in preventing respiratory morbidity in term neonates delivered by elective cesarean section.
PMID: 4000571 [PubMed - indexed for MEDLINE]
 Br J Obstet Gynaecol 1995 Feb;102(2):101-106
Neonatal respiratory morbidity and mode of delivery at term: influence oftiming of elective caesarean section.
Morrison JJ, Rennie JM, Milton PJ.
Department of Obstetrics and Gynaecology, University College London
OBJECTIVE: To establish whether the timing of delivery between 37 and 42 weeks gestation influences neonatal respiratory outcome and thus provideinformation which can be used to aid planning of elective delivery at
DESIGN: All cases of respiratory distress syndrome or transient tachypnoea at term requiring admission to the neonatal intensive care unit wererecorded prospectively for nine years.
SETTING: Rosie Maternity Hospital,Cambridge.
SUBJECTS: During this time 33,289 deliveries occurred at or after 37 weeks of gestation.
MAIN OUTCOME MEASURES: This information enabled calculation of the relative risk of respiratory morbidity for respiratory distress syndrome or transient tachypnoea in relation to mode of deliveryand onset of parturition for each week of gestation at term.
RESULTS: The incidence of respiratory distress syndrome at term was 2.2/1000 deliveries(95% CI; 1.7-2.7). The incidence of transient tachypnoea was 5.7/1000deliveries (95% CI; 4.9-6.5). The incidence of respiratory morbidity wassignificantly higher for the group delivered by caesarean section before the onset of labour (35.5/1000) compared with caesarean section during labour(12.2/1000) (odds ratio, 2.9; 95% CI 1.9-4.4; P < 0.001), and compared with vaginal delivery (5.3/1000) (odds ratio, 6.8; 95% CI 5.2-8.9; P < 0.001). The relative risk of neonatal respiratory morbidity for delivery by caesarean section before the onset of labour during the week 37+0 to 37+6 compared with the week 38+0 to 38+6 was 1.74 (95% CI 1.1-2.8; P < 0.02) and during the week 38+0 to 38+6 compared with the week 39+0 to 39+6 was 2.4(95% CI 1.2-4.8; P < 0.02).
CONCLUSIONS: A significant reduction in neonatal respiratory morbidity would be obtained if elective caesarean section was performed in the week 39+0 to 39+6 of pregnancy.
PMID: 7756199 [PubMed - indexed for MEDLINE]
Semin Perinatol. 2006 Feb;30(1):28-33.
Short-term outcomes of infants born at 35 and 36 weeks gestation: we need to ask more questions.
Escobar GJ, Clark RH, Greene JD.
Division of Research, Perinatal Research Unit, Kaiser Permanente Medical Care Program, Oakland, CA 94612, USA. firstname.lastname@example.org
BACKGROUND: Newborns who are 35 to 36 weeks gestation comprise 7.0% of all live births and 58.3% of all premature infants in the United States. They have been studied much less than very low birth weight infants. OBJECTIVE: To examine available data permitting quantification of short-term hospital outcomes among infants born at 35 and 36 weeks gestation. DESIGN: Review of existing published data and, where possible, re-analysis of existing databases or retrospective cohort analyses. SETTING: Multiple hospitals and neonatal intensive care units in the United States and England. PATIENTS: Premature infant cohorts with infants whose dates of birth ranged from 1/1/98 through 6/30/04. MAIN OUTCOME MEASURES: 1) Death, 2) respiratory distress requiring some degree of in-hospital respiratory support during the birth hospitalization, and 3) rehospitalization following discharge home after the birth hospitalization.
RESULTS: Newborns born at 35 and 36 weeks gestation experienced considerable mortality and morbidity. Approximately 8% required supplemental oxygen support for at least 1 hour, almost 3 times the rate found in infants born at > or =37 weeks. Among 35 to 36 week newborns who progressed to respiratory failure and who survived to 6 hours of age and did not have major congenital anomalies, the mortality rate was 0.8%. Following discharge from the birth hospitalization, 35 to 36 week infants were much more likely to be rehospitalized than term infants, and this increase was evident both within 14 days as well as within 15 to 182 days after discharge. In addition, late preterm infants experienced multiple therapies, few of which have been formally evaluated for safety or efficacy in this gestational age group.
CONCLUSIONS: Greater attention needs to be paid to the management of late preterm infants. In addition, it is important to conduct formal evaluations of the therapies and follow-up strategies employed in caring for these infants.
PMID: 16549211 [PubMed - indexed for MEDLINE]
Full text of Short-term outcomes of infants born at 35 and 36 weeks... by Escobar, Clark and Greene - in pdf format, so requires Adobe Acrobat to view.
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