Bicornuate uterus and fertility

Dear Professor Winston,

Firstly my sincere thanks for offering this service and giving us the chance to have an expert to put these questions to. I found out yesterday that I have become pregnant whilst having the non-hormonal, copper coil in situ. I had today a transvaginal ultrasound which found that the pregnancy is not eptopic, but that I have a bicornuate uterus – the coil was in the left cavity and the baby is in the right. The coil was then removed without repercussions thus far. Is there anything I can do whilst pregnant to maximise the uterine health to reduce the change of miscarriage– be it through a procedure, or lifestyle changes? Or, if this pregnancy is not successful, what options might be available to me to avoid the problem re-occuring? I don’t know the severity of the malformation, is there any benefit in pushing for a hysterosalpingogram at this time to find out? Perhaps just to be better informed about the amount of risk during this pregnancy, and help us manage our expectations? I attended a hospital’s Early Pregnancy Unit and have an appointment there for a follow up ultrasound in two weeks, would a HSG fall under their specialism do you think? I did in fact have a transvaginal ultrasound two years ago after I was bleeding constantly after the coil was inserted (this resolved with Utovlan) which did not detect the uterine malformation, but did detect polycystic ovaries. I have always had quite regular periods, just a slightly longer cycle. The fact that I have had the coil for two years, having sex throughout, and could presumably have fallen pregnant in the right cavity at any time– could this indicate that my fertility is quite low? I am 30 years old and according to my date of last menstruation am 6 weeks and 6 days pregnant. Otherwise I am relatively healthy though slightly overweight (BMI 26). My deepest thanks again, N

Dear N,

Bicornuate uterus is common and frequently goes undetected; ultrasound is not brilliant at picking it up. Unquestionably HSG is the method of choice for diagnosis. It sounds to me as if the defect is quite big in your case if a pregnancy has co-existed with a coil.

The first thing to say is that most people in your situation do not miscarry and give birth normally. Secondly, after you have delivered correction of the defect is usually quite simple in experienced hands, when it is needed if at all. If you do miscarry I would advise a full work-up which includes an HSG and hysteroscopy – but at least three months afterwards when the uterus has settled down.

But as I say, this is not a gloomy situation. You are a bit more likely to go into premature labour, and also a bit more likely to have a malpresentation like a breech presentation – but all this can usually be dealt with completely safely. The risk of having a Caesarean section is rather higher, but nowadays this is a very routine procedure and should not normally be indicated if you go into labour at roughly the right time and with the baby in the right position, head first. After a normal delivery, particular care with delivery of the placenta is quite frequently needed, but many reasonable obstetric unit will be totally capable of dealing with that. May I just say that home confinement is not advisable because your labour will need supervision in hospital for complete safety for the baby.

Your history does not really suggest your fertility is unusually low. The presence of a coil in one side of the uterus would obviously cut your chance of conception by half and the presence of a double uterus will nearly always lower the odds slightly in most cases.

I hope all goes well (which is the most likely outcome).
Robert Winston