Q.98. Which one of the following options is NOT a viable strategy for developing a female
contraceptive? The administration of
(A) a combination of synthetic progesterone and estrogen
(B) synthetic progesterone alone
(C) ormeloxifene – a selective estrogen recepior modulator
(D) a synthetic oxytocin

Female contraceptives primarily work by preventing ovulation, thickening cervical mucus, or altering the uterine lining to block implantation. The correct answer is (D) a synthetic oxytocin, as it induces uterine contractions rather than preventing conception.

Correct Answer

(D) a synthetic oxytocin

Synthetic oxytocin mimics the natural hormone that triggers uterine contractions during labor and milk ejection postpartum. Administering it would promote muscle contractions in the uterus, potentially disrupting rather than preventing pregnancy by facilitating expulsion or implantation issues indirectly, but it lacks any established contraceptive mechanism like ovulation suppression.

Option Explanations

(A) Synthetic Progesterone + Estrogen

Combined oral contraceptives (COCs) containing synthetic versions of both hormones are highly effective. They suppress ovulation by inhibiting FSH/LH surges, thicken cervical mucus to block sperm, and thin the endometrium to prevent implantation. This remains the most common reversible female contraceptive worldwide.​

(B) Synthetic Progesterone Alone

Progestin-only pills (POPs), injectables like DMPA, implants, or IUDs use synthetic progesterone (e.g., levonorgestrel, desogestrel) effectively. They primarily thicken cervical mucus (preventing sperm entry), partially suppress ovulation (up to 97% in some types), and alter endometrial receptivity without estrogen’s risks like thromboembolism.

(C) Ormeloxifene (SERMs)

Ormeloxifene, a selective estrogen receptor modulator (SERM), is a non-steroidal weekly oral contraceptive used in India (e.g., Saheli). It creates asynchrony between ovulation and uterine preparedness by modulating estrogen receptors, delaying endometrial maturation to block implantation without fully halting ovulation.​