Ans. is a i.e. Second trimester Friends, answer to this question was quite obvious as each one of us have mugged it up; but finding an appropriate reference was a difficult task. Read for yourself whatDutta Obs. 6/e, p 309 has to say? "Red Degeneration; It predominantly occurs in a large fibroid during the second half of pregnancy or puerperium." From the above statement answer could be second trimester, third trimester or puerperium. "Red degeneration; manifests typically about midpregnancy when the leiomyoma suddenly become acutely painful, enlarged and tender." This clears the doubts and confirms our answer i.e Red degeneration is most common during second trimester (midpregnancy). Friends you should also keep in mind the following impoant points regarding - Fibroids and pregnancy. Effects of Fibroid on pregnancy : Infeility - Leiomyomas are a sole cause of infeility in less than 30/0 of cases.deg - It causes infeility by : Hindering the ascent of the spermatozoa by distoing the uterus and tubes. By disturbances in ovulation and By interfering with implantation of the feilized ovum. - Pregnancy rate following myomectomy = 40%deg Aboiondeg, Placental abruptiondeg and Premature labourdeg. Occurs when fibroid interferes with enlargement of uterus, initiates abnormal uterine contractions or prevents efficient placentation, Ma!positiondeg and Malpresentationdeg of Fetus : occur as fibroid can prevent engagement of head. Obstructed labour : It can be caused by cervicaldeg and broad ligament tumoursdeg which are fixed in the pelvis and by pedunculated subserous leiomyomas which become trapped in the pouch of Douglas. During labour - If fibroid is situated above the presenting pa - uneventful vaginal delivery. - If fibroid is situated below the presenting pa spontaneous vaginal delivery may occur; otherwise caesarean section is done. Thus chances of cesarean section are increased.deg Post Paum Hemorrhagedeg /Delayed Involutiondeg can occur if placenta is implanteddeg over the leiomyoma. Uterine ineia - Ineia due to fibroid is not suppoed