Table 3

Factors for unintended pregnancy among graduate students active in premarital sex
Factors Male students (n=1831) Female students (n=1059)
Total n (%) IOPa n (%) CORb(95% CI) Total n (%) IOPa n (%) CORb(95% CI)
Educational levels
Master candidate 1467(80.1) 296(20.2) 1 885(83.6) 148(16.7) 1
Doctoral candidate 364(19.9) 77(21.2) 1.06(0.80,1.41) 174(16.4) 40(23.0) 1.49(1.01,2.22)
Discipline
nonmedical 1434(78.3) 299(20.9) 1 818(77.2) 137(16.7) 1
medical 397(21.7) 74(18.6) 0.87(0.66,1.15) 241(22.8) 51(21.2) 1.33(0.93,1.91)
Whether having a steady lover
Yes 1616(88.3) 302(18.7) 1 979(92.4) 156(15.9) 1
No 215(11.7) 71(33.0) 2.13(1.56,2.94) 80(7.6) 32(40.0) 3.57(2.17,5.56)
Disposable income per month
<400(yuan) 360(19.7) 79(21.9) 1.13(0.86,1.58) 184(17.4) 47(25.5) 1.90(1.26,2.87)
400~899 (yuan) 792(43.3) 154(19.4) 1 503(47.5) 77(15.3) 1
≥900(yuan) 679(37.1) 140(20.6) 1.08(0.83,1.39) 372(35.1) 64(17.2) 1.15(0.80,1.65)
Age at first sexual intercourse
<20 years 346(18.9) 91(26.3) 1.53(1.16,2.00) 118(11.1) 39(33.1) 2.62(1.72,4.00)
≥20 years 1485(81.1) 282(19.0) 1 941(88.9) 149(15.8) 1
Whether knowing the conditions of conception
Yesc 1384(75.6) 243(17.6) 1 851(80.4) 134(15.7) 1
No 447(24.4) 130(29.1) 1.93(1.50,2.46) 208(19.6) 54(26.0) 1.88(1.31,2.69)
Whether knowing the use of the menstrual cycle for contraception
Yesd 1087(59.4) 199(18.3) 1 801(75.6) 130(16.2) 1
No 744(40.6) 174(23.4) 1.36(1.08,1.71) 258(24.4) 58(22.5) 1.50(1.06,2.12)
Whether thinking abortion endanger women's physical and mental health
Yes 1452(79.3) 280(19.3) 1 905(85.5) 148(16.4) 1
No 379(20.7) 93(24.5) 1.36(1.04,1.78) 154(14.5) 40(26.0) 1.80(1.20,2.68)
Whether thinking abortion endanger women’s future pregnancy
Yes 1645(89.8) 293(17.8) 1 1007(95.1) 166(16.5) 1
No 186(10.2) 80(43.0) 3.48(2.54,4.78) 52(4.9) 22(42.3) 3.72(2.09,6.62)
Whether use of condoms at first sexual intercourse
Yes 675(36.9) 119(17.6) 1 322(30.4) 27(8.4) 1
No 1156(63.1) 254(22.0) 1.24(1.02,1.51) 737(69.6) 161(21.8) 3.03(2.00,4.76)
Whether use of contraceptives at first sexual intercourse
Yes 1718(93.8) 341(19.8) 1 964(91.0) 168(17.4) 1
No 113(6.2) 32(28.3) 1.60(0.94,2.44) 95(9.0) 20(21.1) 1.26(0.75,2.13)
Frequency of use of contraception(methods were looked as effective for preventing pregnancy by responders)
Always use 548(29.9) 105(19.2) 1.71(0.83,3.55) 358(33.8) 48(13.4) 0.40(0.16,0.91)
Often/sometimes 1209(66.0) 259(21.4) 1.97(0.97,4.01) 676(63.8) 133(19.7) 0.63(0.26,1.53)
Never use 74(4.1) 9(12.2) 1 25(2.4) 7(28.0) 1

a: incidence of pregnancy; b: crude odds ratio; c: students select all correct answers of conditions of conception but no wrong answers from list [detail of information was showed as below: What are the basic conditions for human conception? (Multiple choice) 1, healthy and active sperm can get into the vagina, and remain active force; 2, healthy and mature egg; 3, cervical mucus must be appropriate and conducive to sperm survival and penetration; 4, unobstructed reproductive tract to make the sperm and egg meeting; 5, sperm and egg must combined and formed a fertilized egg; 6, fertilized egg reach the uterine cavity timely, and the intrauterine environment is suitable for the growth and development of fertilized egg. 7, the sex intercourse between male and female. If a student chose answer 1,2,3,4,5 and 6 but no 7,.we considered it as ‘knowing the conditions of conception’, otherwise ‘no’]; d: students select right answers of calculating periodic abstinence and select the answer of periodic abstinence being not completely safe for contraception from list.

Zhou et al.

Zhou et al. BMC Public Health 2013 13:198   doi:10.1186/1471-2458-13-198

Open Data