AUSTIN, Tex (Reuters) - Women seeking an abortion would have to first get an ultrasound under a measure approved on Thursday by the Texas House of Representatives.

The proposal, the first significant bill considered by the House this year, was designated by Republican Governor Rick Perry as an emergency priority. A similar measure has already been approved by the state Senate.

Women would have to get an ultrasound between 24 and 72 hours before an abortion, the bill says. They would view the sonogram, hear an explanation of the image and listen to the heartbeat, if it is audible.

"We want to make sure that they're fully informed, that they understand the medical consequences, the psychological consequences and everything involved in the procedure," said the bill's author, Republican state Rep. Sid Miller.

Opponents said that the requirement would traumatize women already in a difficult situation. During debate on the House floor, bill opponent Rep. Carol Alvarado held up a trans-vaginal probe used for sonograms early in pregnancy to illustrate what she called a "very intrusive process."

"This is not the jelly on the belly that most of you think," said Alvarado, a Houston Democrat. "This is government intrusion at its best."

Democrats tried unsuccessfully to add a series of amendments to the bill. One of those said that if the woman decided not to go through with the abortion, the state would have to pay for the college education for the child. Another, which also would have applied to cases in which the woman decided not to have the abortion, would have allowed women to get a court order to require the father of the child to get a vasectomy.

The House measure still has one formal hurdle to clear, and differences between the House and Senate bills need to be worked out, before the bill can go to Perry for his signature.

Republicans tried unsuccessfully to pass the sonogram proposal in 2007 and 2009. The measure benefitted from a much larger Republican majority in the House this year after the Republican victories in the 2010 elections.

Texas is one of several states with strong Republican legislative majorities proposing additional restrictions on abortion this year.

Eighteen states regulate the provision of ultrasound by abortion providers, according to the Guttmacher Institute. The requirements in those states vary widely; some of them require women to get an ultrasound before an abortion, while others require only that she be offered the chance to see the image if an ultrasound is performed.

(Editing by Greg McCune)