question: My wife's last menstrual period was 7th December. Her period is regular, between 28 to 32-day cycle. We have two children and the last one is 5months old. We use condoms as contraception. The first time we had sex in that month was on 25th December and we didn't notice and condom breakage. We observed that the condoms slipped off on 2nd Jan as well  as on  the 4th. No semen leakage was observed but she took postinor 2 on 3rd Jan as emergency contraception. We are worried perhaps she's pregnant but serum hCG done on 8th January was negative. The registrar in Obs&Gyn prescribed Primolut N for 5 days. We are worried of the contraindications: lactation and suspected pregnancy.  Can we rely on thee serum hCG considering her period ?. Please I need to know your opinion about this. Thank you.