| a) The best time to provide the
next injection is on the same date each month (or a 4 week schedule may be practical for
some programs). This should be emphasized when training the personnel and counseling the
clients. The grace period of combined injectable
contraceptives (CICs) is officially 3 days. If a client comes in after the grace period
(33 days after the previous injection), advise her that delays in obtaining injections
increase the risk of pregnancy. Offering re-injection for a woman who comes in after the
grace period is reasonable for a woman who states that, once beyond the grace period, she
has been abstaining or consistently using a back-up method, or if the provider can be reasonably sure that the woman is not pregnant. Some programs
will advise the woman to use a back-up method for 7 days. |
a) Clinical trials have studied
the efficacy of CICs given 27 to 33 days after the previous injection and found the
efficacy to be very high. Some studies have found that the risk of ovulation is low up to
60 days after the previous Cyclofem or Mesigyna injection.
- Sang G. Pharmacodynamic effects of
once-a-month combined injectable contraceptives. Contraception 1994;49(4):361-85.
- Aedo AR, Landgren BM, Johannisson E,
Diczfalusy E. Pharmacokinetic and pharmacodynamic investigations with monthly injectable
contraceptive preparations. Contraception 1985;31(5):453-69.
- Bassol S, Garza-Flores J. Review of
ovulation return upon discontinuation of once-a-month injectable contraceptives.
Contraception 1994;49(5):441-53.
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| b) The fetus will be exposed to
the injectable's hormones if the woman is pregnant when she receives the next injection. However, there is no evidence that fetal exposure to CICs will be
harmful. |
b) Although the estrogens and
progestins in CICs have no known teratogenic effects, avoiding fetal exposure is
preferable on general principles.
- Simpson JL, Phillips OP. Spermicides,
hormonal contraception and congenital malformations. Advances in Contraception
1990;6:141-67.
- Bracken MB. Oral contraception and
congenital malformations in offspring: a review and meta-analysis of the prospective
studies. Obstetrics and Gynecology 1990;76:552-7.
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