Dear Dr Mitchell,
I had two miscarriages and waited a year to try again. Now I am eight weeks pregnant. My doctor wants to put me on progesterone therapy for the next four weeks to decrease my chances of having another miscarriage, but when I read the side effects, they seem horrible. What exactly does this therapy do, and will it guarantee me a full-term delivery?
A miscarriage may be due to several factors.
In the first 14 weeks, the most common cause of a pregnancy loss is an abnormality in the make-up of the foetus (abnormal chromosomes) which might be due to an abnormal egg or sperm. This accounts for at least 50 per cent of cases.
Other causes of recurrent pregnancy losses include infections such as toxoplasmosis, rubella, cytomegalovirus infection, Herpes Simplex type II, syphilis, and human immunodeficiency virus (HIV).
After the first trimester, uterine abnormalities and a short or weak cervix contribute significantly to recurrent pregnancy losses. The uterine abnormality may be a condition you are born with and may include a septum in the uterus or an abnormal division of the uterus into two separate cavities (bicornuate uterus).
The cavity of the uterus may also be T-shaped and this usually results when mothers take diethylstilbestrol in pregnancy and their female offspring develop this problem. This drug is no longer used and such a finding is now rare in women of child-bearing age.
A weak or short cervix may also be inherited or result when the muscles of the cervix become damaged from surgery. This includes procedures done to terminate pregnancy (induced abortion), dilatation and curettage for other problems in the non-pregnant state, cone biopsy and loop excision of the cervix. This typically results in the painless and complete loss of the pregnancy.
A pregnancy loss can be prevented by the insertion of a stitch in the cervix (cervical cerclage) at the end of the first trimester – about 13-14 weeks.
Progesterone insertion or injections can be beneficial in prolonging the pregnancy by preventing premature contraction of the uterus. This is usually used after insertion of the cervical cerclage or may be used on its own to reduce the risk of a pregnancy loss. The use of progesterone is considered totally safe and any perceived risk is of no significance. It is usually given to women who are known to have recurrent pregnancy or premature labour.
There is no guarantee for any of the methods employed in an attempt to reduce a pregnancy loss. The important thing to do is to determine, as far as possible, the underlying cause of the pregnancy loss and treat the problem to reduce a recurrence.
The use of progesterone insertions can only be beneficial and will definitely be worth the attempt to reduce the risk of another loss. It is important to attend for regular antenatal care and deliver in a hospital with access to intensive care for newborns in the event that you deliver prematurely.
It might also be necessary for you to receive steroidal injections (dexamethasone) in the event that you deliver prematurely.
Consult your doctor who will advise you further and best wishes for an uneventful antenatal course and a safe delivery.
Dr Sharmaine Mitchell is an obstetrician and gynaecologist. Send questions via e-mail to firstname.lastname@example.org ; write to All Woman, 40-42 1/2 Beechwood Ave, Kingston 5; or fax to 876-968-2025. All responses are published. Dr Mitchell cannot provide personal responses.
The contents of this article are for informational purposes only, and must not be relied upon as an alternative to medical advice or treatment from your own doctor.