what are the predisposing factors of cervical incompetence?
1. forceful dilatation of the cervix: eg multiple TOP or D&C, especially in people from abroad. especially TOP in early pregnancy. in UK TOP in early pregnancy is usually medically not surgically managed (misoprostol)
2. management of CIN or cervical carcinoma. LLETZ x 2; cone biopsy especially
3. manchester repair - amputate cervix as Rx of prolapse in a woman that has not completed her family
4. exposure to diethylstilbestrol - used in past to treat early miscarriage
what investigation is used to determine CI and what sign?
funnel shaped cervix
if you suspect CI early in pregnancy, what should be done?
1. cleanse vagina with clindamycin or metronidazole prevent BV and miscarriage
2. USS: measure cervical length. if < 2cm high chance will deliver soon. if < 15mm may miscarry
3. if < 2cm, need to close it so bacteria do not ascend.
what are the 2 types of treatments for CI?
2. progestogens: support
if had a cervical stitch, what are indications for removal?
4. > 37/40
what are the 3 types of cervical cerclage (stitch)?
1. mcdonald cerclage: most common, purse string stitch to shut cervix. band of suture at upper part of cervix, while lower part already started to efface. done 12-34 weeks. removed at 37 weeks
2. shirodkar cerclage: sutures pass through walls of cervix so they're not exposed. closes internal os of cervix. more difficult. may reduce risk of infection.
3. abdominal cerclage: least common, permanent. do if cervix too short for standard cerclage or if vaginal (1, 2) have failed.
aside from cervical incompetence, what 4 things do you want to look at on USS of fetes?
1. abdominal circumference: as eg malnutrition will have small AC as liver glycogen stores are all used up)