Oral Contraceptive Pills & Adoption — NEET Biology

Correct answer: A — S1, S2 and S4

The core concept revolves around the characteristics, mechanism of action, and usage of various contraceptive methods mentioned in the NCERT text. Let's evaluate each statement to identify the incorrect ones: S1: Saheli is a once-a-week oral contraceptive that contains a non-steroidal preparation, not steroidal. Thus, S1 is NOT correct. S2: Progestogens alone or in combination with estrogen can be used as injectables, and their effective periods are much longer than pills. The statement says 'only progestogens' and 'shorter effective period', which are both incorrect. Thus, S2 is NOT correct. S3: Diaphragms, cervical caps, and vaults are indeed reusable barrier methods made of rubber that are inserted into the female reproductive tract to cover the cervix during coitus, preventing sperm entry. Thus, S3 is correct. S4: Emergency contraceptives (progestogens or progestogen-estrogen combinations or IUDs) are very effective if administered within 72 hours of coitus, not 24 hours. Thus, S4 is NOT correct. S5: Vasectomy involves surgically removing or tying up a small part of the vas deferens to block gamete transport, and its reversibility is very poor. Thus, S5 is correct. The statements that are NOT correct are S1, S2, and S4. Option A correctly identifies these statements as incorrect.